• 디지털콘텐츠학회 논문지
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• 제4권2호
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• pp.181-189
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• 2003

분산 멀티미디어 응용에 대한 요구는 정교한 QoS 관리를 위해서 필요하다. 분산 멀티미디어 시스템 견지에서 보면, QoS의 가장 중요한 범주는 시간성, 볼륨, 신뢰성이다. 본 논문에서는 결함 허용을 통해서 신뢰성을 향상시키는 방법에 대해서 기술한다. ECA는 분산 멀티미디어에서 하나의 소프트웨어 오류를 자동적으로 분류할 수 있는 시스템이다. 본 논문은 규칙-기반 DEVS 모델링과 시뮬레이션 기법을 사용하면서 분산 멀티미디어 상에서의 오류 분류 시스템의 성능 분석을 설명한다. DEVS에서 하나의 시스템은 시간, 입력, 상태, 출력 및 함수들을 가지고 있다.

• 센서학회지
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• 제28권5호
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• pp.277-283
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• 2019

In this paper, we propose a distributed fusion estimation for sensor networks using a receding horizon strategy. Communication channels were modelled as Markov jump systems, and a posterior probability distribution for communication channel characteristics was calculated and incorporated into the filter to allow distributed fusion estimation to handle path loss observation situations automatically. To implement distributed fusion estimation, a Kalman-Consensus filter was then used to obtain the average consensus, based on the estimates of sensors randomly distributed across sensor networks. The advantages of the proposed algorithms were then verified using a large-scale sensor network example.

• 한국정보처리학회논문지
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• 제6권11호
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• pp.3034-3045
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• 1999

For efficiently providing multimedia services, distributed computing environments are specified the requirements of various services and distributed object platforms applied an object-oriented technology by TINA Consortium and OMG CORBA. Because multimedia service applications are becoming large and distributing, their servicing managing interfaces among objects are being complicated. In order to solve these defects, it is necessary to suggest a new object grouping model and specify object service/management requirements can be introduced under the object groups. We have been developed the distributed object group platform that can group all individual objects by the relating services and can supply trading functions for interconnecting between distributed objects or object groups. In this paper, we designed and implemented the Virtual Drawing Board for remote equational services on the distributed object group platform we mentioned above. As results, we designed a basic structure and service interfaces, and showed execution procedures of VDB system consisted of distributed objects and objects groups for educational services. For supporting distributed services of VDB system, we used three kinds of tools as follows; IONA orbix 2.2 of CORBA compliance as an object middleware, OrbixTrader 1.0 for interconnection of distributed objects, and the OGTG we developed for interconnection of distributed object groups and checking access rights of objects included in an arbitrary object group.

• 전기학회논문지
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• 제59권2호
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• pp.298-305
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• 2010

In this paper, a new algorithm of optimal Volt/Var Control is proposed using Volt/Var control for the Distribution Automation System (DAS) with Distributed Generation (DG) based on the modeling of the distributed load and the distributed current. In the proposed, algorithm based on the modeling of the distributed load and the distributed current are estimated from constants of four terminals using the measurement of the current and power factor from a Feeder Remote Terminal Unit (FRTU) and DG data from RTU for DG. For the optimal Volt/Var Control, the gradient method is applied to find optimal solution for tap, capacity and power control of OLTC (On-Load Tap Changers), SVR (Step Voltage Regulator), PC (Power Condenser) and DG (Distributed Generation). In the case studies, the estimation and control of the voltages have been testified in a radial distribution system with DG using matlab program.

• 정보처리학회논문지D
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• 제11D권6호
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• pp.1301-1310
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• 2004

물리적으로 분산된 개발자들은 분산 페어 프로그래밍 지원 시스템을 활용하여 페어 프로그래밍을 수행할 수 있다. 하지만 원격 화면 공유기능 위주의 기존 CSCW 기반의 분산 페어 프로그래밍 지원 시스템들은 많은 개발자들이 분산 페어 프로그래밍을 수용하기에는 사용의 접근성, 용이성 등의 측면에서 미흡한 점이 많다. 본 논문에서 우리는 소프트웨어 개발자들이 분산 페어 프로그래밍을 수용하기 적합한 형태의 시스템 모델로서 IDE(Integrated Development Environment) 기반의 분산 페어 프로그래밍 시스템을 제안한다. 본 시스템의 GUI와 사용자 시나리오는 분산 페어 프로그래밍이 용이하도록 개발되었으며 디자인 패턴 을 적용하여 확장성이 높도록 시스템을 설계하고 자바언어로 구현하였다. 본 연구결과는 기존의 상업용 IDE에서 분산 페어 프로그래밍 기능과 GUI를 구현하는 개발자들에게 도움이 될 것이다.

• 한국컴퓨터정보학회논문지
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• 제12권6호
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• pp.1-9
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• 2007

본 논문에서는 분산된 자원 관리를 위한 새로운 프레임워크를 제안한다. 제안된 프레임워크는 새로운 특징들을 가진다. 첫째로, 자원 관리 시스템은 시스템 속성에 의해 특징지어지는 자원 컨텐츠 정보를 사용하여 분산되어진다. 자원 컨텐츠에 의거하는 분산 시스템은 그리드를 통해 워크로드 균형을 고려한다. 또한 Quality of Service(QoS)를 위한 특수한 스케줄링 요청을 만족시킨다. 두 번째로. 분산 시스템은 계층적 peer-to-peer 네트워크를 구성한다. 이러한 peered 네트워크는 효과적인 메시지 라우팅 메커니즘을 제공한다. 제안된 프레임워크가 시뮬레이션을 통하여 분산 환경에서 QoS를 만족한다는 것을 증명하고 있다.

• 대한기계학회논문집A
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• 제23권6호
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• pp.922-930
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• 1999

This paper describes a new 14-CPU real-time distributed automatic gauge control (AGC) system for POSCO's No. 2 Hot Strip Mill at Pohang Works. The new AGC system has adopted gaugemeter AGC, Monitor AGC, and roll gap disturbance compensators. The computer system for the new AGC system has been developed based on VMEbus computer systems and a commercial real-time operating system. A VMEbus computer system is also used for the position servo control of hydraulic cylinders. All the application programs and input/output signals have been reasonably distributed over the control computer systems for the maximum reliability and effectiveness of the system. The new AGC system has been successfully used for the No. 2 Hot Strip Mill.

• Journal of Electrical Engineering and Technology
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• 제7권4호
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• pp.486-492
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• 2012

This paper presents a novel objective function for distribution system reconfiguration for reliability enhancement. When islanding operations of distributed generators is prohibited, faults in the feeder interrupt the operation of distributed generators. For this reason, we include the customer interruption cost as well as the distributed generator interruption cost in the objective function in the network reconfiguration algorithm. The network reconfiguration in which genetic algorithms are used is implemented by MATLAB. The effect of the proposed objective function in the network reconfiguration is analyzed and compared with existing objective functions through case studies. The network reconfiguration considering the proposed objective function is suitable for a distribution system that has a high penetration of distributed generators.

• 조명전기설비학회논문지
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• 제29권1호
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• pp.113-120
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• 2015

Network type distributed control system uses a communication line which is named the BUS to exchange a data among the sub-systems. Usually, on the bus, only one data must be exited at one time, so the control algorithm to prevent collision or to manage a priority of data is important. Including CAN Protocol, many kind of FieldBus which are used for distributed control system, prevent data collision by controlling transmission time. But, a system which have to make a control signal or get a data from a sensor at fixed time will be met a problem when it is composed by using a network type distributed control structure. In this paper, some of these cases will be discussed and solutions be proposed for preventing a data collision. Also, using Arago Disk System which have a structure for inner loop control, the validity of the proposed methods will be verified.

• 대한전기학회논문지:전력기술부문A
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• 제54권11호
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• pp.518-524
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• 2005

This paper presents an analytical method for the reliability evaluation of distribution system, including the distributed generations. Unlike the large sized generations of transmission system, the distributed generations have complexities in analyzing and determining the operation. In the process of evaluate reliability, it can be shown that the analytical method is simpler than the Monte-Carlo simulation and the method using Load Duration Curve model is more accurate than that using peak load model. The modeling of distributed generation to analysis distribution system reliability using LDC is proposed in this Paper, and is compared with the MCS method as a result of case studies.